The role of glitazones in management of type 2 diabetes. A dream or a nightmare?

Glitazones have been introduced as second-step medication for type 2 diabetics, and today rosiglitazone and pioglitazone are blockbuster drugs. However, glitazones may have important adverse effects that outweight their beneficial effect on insulin resistance and glycemia. The larger trials have shown that glitazones produce a weight gain of 4-5 kg over 3-4 years of treatment, and the weight gain cannot be explained by fluid retention. Moreover, the risk of myocardial infarction is increased by 43% by rosiglitazone, and there are clear indications of increased risk of heart failure. Furthermore, there are studies to suggest that glitazones also increase the risk of fractures, whereas an increased cancer risk is not supported. In conclusion, given the increased cardiovascular risk, and that a weight gain of few kg can increase risks of cancer of the breast, colon, prostate and endometrium, the use of glitazones should be questioned. There is a need for more safe and weight neutral drugs to treat type 2 diabetes.